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The Use Of Simulation To Evaluate Strategic Aeromedical Evacuation Policy And Planning, Charles W. Wolfe Jr. Mar 1993

The Use Of Simulation To Evaluate Strategic Aeromedical Evacuation Policy And Planning, Charles W. Wolfe Jr.

Theses and Dissertations

Strategic aeromedical evacuation (AE) of casualties from the theater of operations to the CONUS during wartime is a complex operation that involves the integration of medical personnel and policies with airlift concepts and capabilities. Military analysts within the Air Mobility Command Analysis Group (AMC/XPY) have traditionally used deterministic linear programming techniques to estimate the number of aircraft the United States Air Force (USAF) requires for given contingency scenarios. However, this group has yet to develop a stochastic approach to validate their resource recommendations, and more importantly, to study the interrelationships between key factors comprising strategic aeromedical evacuation. As the possibility …


Patient Scheduling And Aircraft Routing For Strategic Aeromedical Evacuation, Michael J. Loftus Mar 1993

Patient Scheduling And Aircraft Routing For Strategic Aeromedical Evacuation, Michael J. Loftus

Theses and Dissertations

The objective of this study is to develop an approach that would assign patients to aeromedical evacuation aircraft and route each aircraft to a single CONUS airport. The goal is to minimize total patient wait time. A heuristic algorithm is developed which exploits the structure of the problem. The first subproblem solved is the assignment of aircraft to airports. This subproblem is solved using integer programming and the results are input into the second subproblem. The second subproblem is the patient to aircraft assignment problem. This subproblem minimizes patient wait time and is solved using network flow programming. The two …


The Airlift Capabilities Estimation Prototype: A Case Study In Model Validation, Randy Mccanne Mar 1993

The Airlift Capabilities Estimation Prototype: A Case Study In Model Validation, Randy Mccanne

Theses and Dissertations

This study investigates the application of a life cycle approach to the validation of operational models. The classic waterfall life cycle from software engineering is adapted for use on mathematical models by defining four stages of model development. Each stage is discussed in detail and examples of the output from each stage are presented. In addition, techniques are investigated for applying the proposed life cycle to existing models through the recovery of life cycle stages. The methodology is applied to a linear programming model developed for planning airlift operations to demonstrate the power of the life cycle approach to validation. …


Determining Cargo Flow For Air Mobility Command's Channel Cargo System., Michael Del Rosario Mar 1993

Determining Cargo Flow For Air Mobility Command's Channel Cargo System., Michael Del Rosario

Theses and Dissertations

This research investigated using a multiperiod multicommodity minimal cost flow (M2MCF) formulation to model the channel cargo system of the United States Air Force's Air Mobility Command (AMC). The objective of this research was to determine how cargo should flow in the channel cargo system in order to minimize the cargo's delay enroute from its origin to its destination. This research showed the size of an M2MCF model of the channel cargo system exceeds AMC's computational capabilities. Additionally, this research describes three approaches to reduce the problem size. Because of the problem size and other modeling limitations discovered during this …


Rendering The Out-The-Window View For The Afit Virtual Cockpit, W. Dean Mccarty Mar 1993

Rendering The Out-The-Window View For The Afit Virtual Cockpit, W. Dean Mccarty

Theses and Dissertations

The Air Force Institute of Technology (AFIT) is developing a distributed interactive flight simulator, the Virtual Cockpit, using commercial graphics workstations and helmet mounted displays. The Virtual Cockpit communicates with other simulators via local and long-haul networks using the SIMNET protocol. The work reported in this thesis focuses on developing the terrain database for the synthetic environment and on rendering the pilot's view of the database. There are many different file formats for describing 3- dimensional geometric polygonal objects. An analysis of three formats, AFIT GEOM, the Naval Postgraduate School (NPS) DRP, and Software Systems' Flight, is presented. Each file …


The Integration Of Tanker Aircraft Into Aslar, John S. Stieven Mar 1993

The Integration Of Tanker Aircraft Into Aslar, John S. Stieven

Theses and Dissertations

The purpose of this study was to analyze the proposed addition of heavy KC-135 tanker aircraft to the United States Air Force Aircraft Surge Launch and Recovery (ASLAR) instrument approach system. The Air Force Communications Command, which oversees ASLAR operations, will use these results to determine if KC-135 aircraft should be permitted to fly ASLAR approaches. A SIMSCRIPT II.5 animated simulation model was developed to simulate the Runway 26 approach at Seymour Johnson Air Force Base under a variety of wind conditions. This model was expanded to show the feasibility of KC-135s flying ASLAR approaches and to determine proper controller …


Scheduling Air Mobility Command's Channel Cargo Missions, Gregory S. Rau Mar 1993

Scheduling Air Mobility Command's Channel Cargo Missions, Gregory S. Rau

Theses and Dissertations

Through the use of a linear programming model, this research revised the initial schedule for AMC's channel cargo missions to eliminate any excess delay enroute by minimizing the cumulative, weighted time-in-system for all cargo, according to a given cargo flow. In fact, the revised schedule minimizes any assigned nonnegative weighting of the time-in-system, due to the properties of equivalent measures of performance. When combined with Step One of a proposed two-step process for revising AMC's channel mission schedule, this research can be used to improve the current schedule based on Step One's cargo flow. By carefully defining the notation and …


An Analysis Of Tactical Airlifter Characteristics And Their Impact On Theater Airlift System Performance, John J. Koger Mar 1993

An Analysis Of Tactical Airlifter Characteristics And Their Impact On Theater Airlift System Performance, John J. Koger

Theses and Dissertations

This study used computer simulation and Response Surface Technology to determine what tactical airlifter characteristics most impact theater airlift system performance in a Southwest Asia (SWA) scenario. Some Aircraft characteristics were grouped into functional sets, while others were considered individually. After screening one characteristic, reliability, with a two-level factorial experiment, a Box-Behnken design was used to estimate second-order metamodels. A stepwise regression procedure indicated that, if attrition rates are ignored, airlift system performance is most impacted by the aircraft's size, survivability, cruise speed, and ability to operate on short fields. The SWA scenario used in this study covers a large …


Models For The Optimization Of Air Refueling Missions, Clayton H. Pflieger Mar 1993

Models For The Optimization Of Air Refueling Missions, Clayton H. Pflieger

Theses and Dissertations

This research follows A. Yamani's work on the problem of minimizing total fuel costs for airlift missions that require in-flight refueling. Yamani's major assumptions were removed and the resulting enhanced formulation was applied the the original problem and the related problem of maximizing allowable cabin load. This optimization is accomplished selecting the rendezvous point and initial fuel for each aircraft. The formulation considers a C-141B airlifter refueled once by a KC-135E tanker. Flight is assumed to be at constant altitude and follow great-circle routes. The fuel costs of climb and cruise flight are modeled as functions of gross weight, while …


Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr. Jan 1993

Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr.

Theses and Dissertations

The Air Force Institute of Technology is continuing research in the Virtual Cockpit. The Virtual Cockpit makes use of high performance graphics workstations, Virtual Environment technology, and Distributed Interactive Simulation network protocols to create a flight simulator based on the capabilities of the McDonnell Douglas F-15E Strike Eagle. The work presented in this thesis focuses on the design and implementation issues for integrating a weapons delivery capability. Weapons simulated include: RADAR and IR guided air- to-air missiles, gravity and precision guided bombs, and a 20mm cannon. Virtual Environment displays used include: color NTSC and monochrome high resolution helmet mounted displays …


Automated Control Of Aircraft In Formation Flight, Louis E. Buzogany Dec 1992

Automated Control Of Aircraft In Formation Flight, Louis E. Buzogany

Theses and Dissertations

In this study, an automated formation control system for an aircraft formation comprised of one lead and multiple wing aircraft is analyzed. Second- order models of the C-130 aircraft are developed in order to accurately model the flying qualities of large aircraft. This automated formation control system is capable of controlling the C-130 aircraft in maneuvering formation flight, thus reducing the wing's pilot workload. During formation flight, the wing aircraft continuously measures the lead aircraft's relative position with an ideal on-board position sensor. This information, in addition to Proportional Plus Integral feedback control, is used to maintain the aircraft in …


Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola Dec 1992

Satcom General Purpose Modem Dscs Iii Sct Beacon Telemetry Display, James D. Coppola

Theses and Dissertations

This thesis documents the design and implementation of a DSCS III single Channel Transponder (SCT) beacon telemetry display. The system is a personal computer based design which interfaces to three SCT beacon receiver/demodulators. The software was designed to decode and display both the DSCS III A and DSCS HI B satellite beacons. Recordings of the SCT beacon display can be made on paper and/or magnetic media when triggered by the user, a watchdog timer, or the SCT command accept telemetry bit. In addition, the system can be configured with an IRIG B Universal Time Coordinates (UTC) card which enables the …


A Synthetic Environment Flight Simulator: The Afit Virtual Cockpit, John C. Switzer Dec 1992

A Synthetic Environment Flight Simulator: The Afit Virtual Cockpit, John C. Switzer

Theses and Dissertations

This thesis describes the design and implementation of a part of the Virtual Cockpit: a synthetic environment, distributed network flight simulator. The goal of the project was to prove the concept that this type of flight simulator could fill the gap between high-end, very expensive flight simulators and low-end game quality flight simulators. Discussed are: object-oriented design techniques, multi-processor utilization, the flight dynamics model, synthetic environment technology, the frame-rate vs. realism issue, and the interfaces to a realistic joystick and throttle.


Study Of Longitudinal Landing Flying Qualities Evaluation Using Pilot Model Theory, Eric D. Didomenico Dec 1984

Study Of Longitudinal Landing Flying Qualities Evaluation Using Pilot Model Theory, Eric D. Didomenico

Theses and Dissertations

Control Anticipation Parameter (CAP), used in MIL-SPEC-8785C as a longitudinal handling qualities criterion does not adequately distinguish between different flight phases. Recent flight test data from the Landing Approach Higher Order Systems (LAHOS) study further indicate the inadequacy of the second order approximations for higher order longitudinal landing flying qualities. Nine Aircraft that fall within the Level 1 boundary reveal pilot ratings ranging from 1.5 to 10 (Cooper/Harper). These nine aircraft are studied by combining their longitudinal dynamics with pilot modelling to examine a better method of landing flying quality prediction and evaluation. Pilot model theory (cross-over pilot model) is …